Drive circuit device for inductive load
US4845420A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 27, 1988 |
| Grant date | Jul 4, 1989 |
| Priority date | — |
| Expiry date | Sep 27, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K17/0422
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In a drive circuit device for an inductive load, the inductive load and a detecting resistor are incorporated in a current supply circuit in series relation to a drive transistor. An operational amplifier is operative in response to detecting voltage fed-back from the detecting resistor, for controlling the drive transistor, in turn, for controlling supply current flowing through the inductive load to a predetermined value. Turning-on and -off of the drive transistor are controlled by a switching element operative in response to a control signal, thereby carrying out current supply to an inductive load and stoppage of the current supply. A feed-back circuit is provided, in which a response element supplies feed-back current to be controlled by the operational amplifier, to the feed-back resistor, in response to the turning-off of the drive transistor. The operational amplifier carries out feed-back control without being saturated, even at the stoppage of the current supply to the inductive load.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.